4598 - Administration of chemotherapy for metastatic breast cancer near the end of life: a population registry study

Background

The majority of patients with metastatic breast cancer (MBC) receive non-targeted cytotoxic chemotherapy during their disease trajectory. Its use however near the end of life has not been extensively studied and it’s possible that patients with advanced disease may be exposed to unnecessary aggressive treatment.

Methods

Patients who were diagnosed with MBC in 2010-2015 were identified from the Stockholm-Gotland Breast Cancer Registry. Data regarding tumor characteristics, date of MBC diagnosis and death were collected from the registry. Data on chemotherapy use during the final month of the patient’s life, type of chemotherapy regimen used and albumin levels – a surrogate marker for performance status – were collected from individual patient files. Analysis of overall survival of the entire cohort was made in order to estimate contemporary survival of MBC patients.

Results

In total, 1571 patients were identified. Out of 1559 patients included in the survival analysis, there were 1357 deaths and 202 patients still alive. Chemotherapy during the last month of life was given to 23.2% of the patients, more commonly to patients ≤60 years old (35.6% versus 18.5%, p < 0.001). A new treatment regimen was initiated in 8.4% of patients. Both albumin (OR 0.95, 95% CI 0.92 – 0.98, p = 0.002) and age at the time of diagnosis (OR 1.04, 95% CI 1.02 – 1.05, p < 0.001) predicted the administration of chemotherapy. The most commonly used chemotherapeutic was capecitabine (24.8%), followed by paclitaxel (14.6%) and vinorelbine (9.8%). After a median follow-up of 73.4 months, median overall survival in the entire cohort was 16.73 months (95% CI 15.22–18.24); patients ≤60 years-old had better median survival compared to older ones (24.83, 95% CI 20.61-29.05 versus 13.86 months, 95% CI 12.72-15.74; p < 0.001).

Conclusions

Chemotherapy use near the end of life was common, especially among younger patients. Median overall survival at the population level is considerably worse as compared to results from randomized trials. This may reflect on the differences in patient characteristics and completeness of registry data, which include patients that were never treated for MBC.

Clinical trial identification

Editorial acknowledgement

Legal entity responsible for the study

The authors.

Funding

Has not received any funding.

Disclosure

J. Bergh: Research grant / Funding (institution): Merck; Research grant / Funding (institution): Amgen; Research grant / Funding (institution): Bayer; Research grant / Funding (institution): Roche; Research grant / Funding (institution): Pfizer; Research grant / Funding (institution): Sanofi-Aventis; Honoraria (self): UpToDate. T. Foukakis: Honoraria (self), Research grant / Funding (institution): Roche; Honoraria (self), Research grant / Funding (institution): Pfizer; Honoraria (self): Novartis; Honoraria (self): UpToDate. All other authors have declared no conflicts of interest.